ABSORPTION. 



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vital properties of the epithelial cells are in some way concerned in the 

 absorption not only of fat, but of sugar, peptone, and salts. Lannois 

 found that by the injection of alcohol into exposed loops of intestine the 

 epithelial cells were destroyed, and the absorption of oil, sugar, peptone, 

 and mineral salts was delayed. The tendency of opinion of late has 

 been in favor of the epithelial cell as an active factor in absorption, as 

 it is in secretion. 



M. Leubuscher has made some experiments which seem to confirm 

 this view. He found in isolated loops of intestine that the absorption of 

 25 to 50 per cent, solutions of salt took place just as rapidly as that of 



...af 



Fie. 167.— Section of Intestine of Dog showing the Villi. {Cadiat.) 



The blood-vessels, c, and the lacteals, d, have been injected. The blind ending, or simple loop of the black 

 lacteal, is seen to be surrounded by the capillary net-work of the blood-vessels. 



pure water, — a phenomenon which would not take place if the law of 

 diffusion were the sole factor in the process. The salts of sodium were 

 absorbed more rapidly than the salts of potassium, and absorption was 

 not hastened by the presence of bile— contrary to the general belief. 



Grumelewski made a somewhat similar series of experiments, and 

 reached much the same conclusion. Strong solutions of sulphate of 

 sodium increase the rapidity of absorption. 



Hofmeister, especially, has identified himself with the theory that 

 the absorption of peptone is not a purely mechanical process of diffusion 

 or filtration, but that it represents a function of certain living cells or 



